A fiber-reinforced plastic is composed of a thermosetting resin such as an unsaturated polyester resin or an epoxy resin or a thermoplastic resin such as polyamide or polyphenylene sulfide (PPS) and a fibrous filler such as a carbon fiber or a glass fiber, and is lightweight and has excellent mechanical properties, and thus the fiber-reinforced plastic has widely been used in sporting goods applications, aerospace applications and general industrial applications.
There have been made many proposals of adding a glass fiber for the purpose of improving the rigidity of plastics (see, for example, Patent Literature 1). However, these fiber-reinforced plastics may be fractured to expose a sharp fracture surface, leading to scattering of fractured pieces to the surroundings. There is a risk of users getting hurt by such sharp fracture surface due to brittle fracture, thus causing a problem such as limitation of applications.
Thus, there has been proposed a fiber-reinforced polyamide in which a modified elastomer is added for the purpose of improving the toughness of fiber-reinforced plastics (see, for example, Patent Literature 2).